i have noticed that over the last couple of weeks that my fuel milage has dropped . i have not changed my driving habits. i also do not have any codes.i am hoping that some one will have some kind of idea as to where i can look to find the problem. any help is greatly appreciated. the truck in question is a 04.5 3500

 

My guess- Fuel filter. When ever mine is dirty, the mileage drops fast...

 

already done that one.thanks

 

air filter

 

Tire pressure?

Dragging brakes?

Extra weight in the truck?

Driving in windy conditions?

 

Bad injectors. I had 2 that were "under performing". After they replaced them my mileage went up a little more than 2.5 mpg. Basically back to normal.

 

T-boe, how did you know to check the injeectors? Anything that grabbed your attention?

 

If you've seen my other thread about white smoke and rough idle that's pretty much how. I figured the injectors would be to blame I just needed to confirm it with the guys on here.

 

i have had all the normal stuff done like the air filter,fuel filter, brakes.last month i had the engine harness relaced and they done diagnostics on all systems and they said it is all within specs.

 

i just thought of someting. what about a worn clutch?

 

If it was bad enough to cause a change in fuel mileage you'd know it.